Apple Computer's AirPort Utility, Version 6.0 was criticized this week at the North American IPv6 Summit for no longer being compatible with IPv6. The previous Version, 5.6, offered IPv6 service by default. "Comcast, for example, is urging its subscribers that are interested in using IPv6 not to upgrade to AirPort Utility Version 6.0 if they use the OS X Lion operating system because of incompatibilities with IPv6."